Influence of medium amino acids on the ouabain sensitive and insensitive 86Rb+-fluxes in HeLa cells

Components of the 86Rb+-influx in HeLa cells were investigated in Joklik minimal essential medium, or in Earle's balanced salt solution with and without medium amino acids. The presence of amino acids led to the stimulation of the ouabain sensitive 86Rb+-uptake and inhibition of the diuretic-sensitive and residual 86Rb+-fluxes. These results show that the presence of amino acids is an important regulator of the K+/Rb+-fluxes under normal conditions in growth medium.